文献类型：期刊文献

中文题名：石英含量对页岩力学特性及能量演化的影响

英文题名：Influence of Quartz Content on the Mechanical Properties and Energy Evolution of Shale with

作者：王爽 邬忠虎 陈筠 唐摩天

第一作者：王爽

机构：[1]贵州大学资源与环境工程学院,贵阳550025;[2]贵州大学喀斯特地质资源与环境教育部重点实验室,贵阳550025;[3]贵州大学土木工程学院,贵阳550025;[4]贵州理工学院继续教育学院,贵阳550003

第一机构：贵州大学资源与环境工程学院,贵阳550025

年份：2022

卷号：22

期号：19

起止页码：8279-8288

中文期刊名：科学技术与工程

外文期刊名：Science Technology and Engineering

收录：CSTPCD;;北大核心:【北大核心2020】；

基金：国家自然科学基金(52104080);贵州省科学技术基金([2021]401)。

语种：中文

中文关键词：石英含量;页岩储层;黔北地区;能量演化;单轴压缩

外文关键词：quartz content;shale reservoirs;northern Guizhou;energy evolution;uniaxial compress

摘要：石英作为页岩中最主要的矿物成分,研究其含量对页岩储层力学性质和压裂起裂机制具有重要意义。通过X射线衍射仪分析黔北地区下寒武统牛蹄塘组五个页岩样品矿物组分,采用INSTRON 1346电液伺服控制材料试验机(200T)对岩样进行单轴压缩试验,并分析不同石英含量页岩在单轴压缩条件下的能量演化特征。研究表明:①样品石英含量均超过49%,最高可达81.3%,石英含量与脆性指数拟合为R^(2)=0.933;②岩样1和5的应力-应变曲线无屈服阶段,呈典型的塑-弹性型,且裂纹扩展多而复杂,而岩样2、3和4的破坏面几乎垂直贯穿整个岩样,且连续性好而简单;③石英和黏土矿物含量与弹性模量分别呈正负相关,其拟合指数分别为0.88和0.73;④能量演化趋势可划分为平缓-上凹-近线性增长和跌落4个阶段,岩样受压过程中消耗能比弹性应变能大,且低石英含量的岩样吸收总能量普遍要比高石英含量大。本文所取得的研究进一步完善石英含量对页岩储层力学性质和压裂改造的认识,并加深页岩受压破坏过程能量演化的了解。
As the most dominant mineral component in shale,the study of quartz content is important for the mechanical properties and fracture initiation mechanism of shale reservoirs.The mineral composition and content of five shale samples from the Lower Cambrian Niutitang Formation in northern Guizhou were analyzed by using X-ray diffraction(XRD),and the samples were subjected to uniaxial compression tests using an INSTRON 1346 electro-hydraulic servo-controlled material testing machine(200T),and the energy evolution characteristics of the shales with different quartz contents under uniaxial compression conditions were analyzed.Results indicate these as follows the quartz content exceeds 49%in all cases,up to 81.3%,and the quartz content fits the brittleness index at R^(2)=0.933.The stress-strain curves of rock samples 1 and 5 have no yielding phase and show a typical plastic-elastic type,and the crack extensions are multiple and complex.In contrast,the disruption surfaces of rock samples 2,3,and 4 penetrate almost vertically throughout the sample with good and simple continuity.The quartz and clay mineral contents were positively and negatively correlated with the modulus of elasticity with correlation fit indices of 0.88 and 0.73,respectively.The energy evolution trend can be divided into four stages:gentle-up concave-near-linear growth and fall.The energy consumed during compression of the rock sample is greater than the elastic strain energy,and the total energy absorbed by rock samples with low quartz content is generally higher than that of high quartz content.The research achieved in further refines the understanding of quartz content on the mechanical properties and fracturing modifications of shale reservoirs,and deepens the knowledge of the energetic evolution of shale damage processes under pressure.